Über die Kondensation von Benzoin und Resorcin

Zusammenfassung Die Kondensation von Benzoin und Resorcin wurde durch Verwendung von Borsäureanhydrid bedeutend verbessert; ferner wurden einige Derivate des 6-Hydroxy-5-benzoyl-2,3-diphenyl-cumarons und des 4,6-Dihydroxy-1,3-benzoyl-benzols hergestellt und beschrieben.Herrn Prof. Dr.A. Wacek zum 60. Geburtstag gewidmet.1. Mitteilung:O. Dischendorfer, Mh. Chem.62, 263 (1933).     

Use of the Raman spectrometer in gemmological laboratories: review

The current paper gives an overview of the development of Raman spectrometry in gemmological laboratories. While before 1990s, no commercial gemmological laboratory possessed such an instrument, all larger international labs have acquired these instruments by now. The Raman spectrometer is routinely used for the detection of emerald fillers, HPHT treatment of diamonds, analysis of the nature of a gemstone, analysis of gemstone inclusions and treatments, and the characterisation of natural or colour enhanced pearls and corals. Future developments in gemstone research lie in the closer analysis of the features of Raman and PL spectra and in the combination of several instruments.     

An improved gas chromatography screening method for doping substances using triple quadrupole mass spectrometry, with an emphasis on quality assurance

A GC‐QqQ‐MS method was developed for the detection of over 150 compounds from different classes (steroids, narcotics, stimulants, β‐blockers, β‐2‐agonists and hormone antagonists) in a qualitative way. In the quantitative part, the traditional steroid profile with the most important endogenous steroids is expanded with six minor metabolites, which further improves the detection and identification of endogenous steroid abuse. In addition to these, norandrosterone, salbutamol and the major metabolite of cannabis are also quantified. Methods developed for anti‐doping purposes should be subjected to the highest level of quality. Here, the addition of a combination of (deuterated) internal standards allows for an accurate quality control of every single step of the methodology: hydrolysis efficiency, derivatization efficiency and microbiological degradation are monitored in every single sample. Additionally, special attention is paid to the relationships between parameters indicating degradation by micro‐organisms and the reliability of the steroid profile. The impact of the degradation is studied by evaluation of the quantities and percentages of 5α‐androstane‐3,17‐dione and 5β‐androstane‐3,17‐dione. The concept of measurement uncertainty was introduced for the evaluation of relative abundances of mass‐to‐charge ratios and the obtained ranges were compared with the World Anti‐Doping Agency regulations on tolerance windows for relative ion intensities. The results indicate that the approaches are similar. Copyright © 2012 John Wiley & Sons, Ltd.